// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2014 Benoit Steiner (benoit.steiner.goog@gmail.com)
//
// This Source Code Form is subject to the terms of the Mozilla
// Public License v. 2.0. If a copy of the MPL was not distributed
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.

#ifndef EIGEN_COMPLEX_AVX_H
#define EIGEN_COMPLEX_AVX_H

namespace Eigen {

namespace internal {

    //---------- float ----------
    struct Packet4cf
    {
        EIGEN_STRONG_INLINE Packet4cf() {}
        EIGEN_STRONG_INLINE explicit Packet4cf(const __m256& a) : v(a) {}
        __m256 v;
    };

#ifndef EIGEN_VECTORIZE_AVX512
    template <> struct packet_traits<std::complex<float>> : default_packet_traits
    {
        typedef Packet4cf type;
        typedef Packet2cf half;
        enum
        {
            Vectorizable = 1,
            AlignedOnScalar = 1,
            size = 4,
            HasHalfPacket = 1,

            HasAdd = 1,
            HasSub = 1,
            HasMul = 1,
            HasDiv = 1,
            HasNegate = 1,
            HasSqrt = 1,
            HasAbs = 0,
            HasAbs2 = 0,
            HasMin = 0,
            HasMax = 0,
            HasSetLinear = 0
        };
    };
#endif

    template <> struct unpacket_traits<Packet4cf>
    {
        typedef std::complex<float> type;
        typedef Packet2cf half;
        typedef Packet8f as_real;
        enum
        {
            size = 4,
            alignment = Aligned32,
            vectorizable = true,
            masked_load_available = false,
            masked_store_available = false
        };
    };

    template <> EIGEN_STRONG_INLINE Packet4cf padd<Packet4cf>(const Packet4cf& a, const Packet4cf& b) { return Packet4cf(_mm256_add_ps(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet4cf psub<Packet4cf>(const Packet4cf& a, const Packet4cf& b) { return Packet4cf(_mm256_sub_ps(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet4cf pnegate(const Packet4cf& a) { return Packet4cf(pnegate(a.v)); }
    template <> EIGEN_STRONG_INLINE Packet4cf pconj(const Packet4cf& a)
    {
        const __m256 mask =
            _mm256_castsi256_ps(_mm256_setr_epi32(0x00000000, 0x80000000, 0x00000000, 0x80000000, 0x00000000, 0x80000000, 0x00000000, 0x80000000));
        return Packet4cf(_mm256_xor_ps(a.v, mask));
    }

    template <> EIGEN_STRONG_INLINE Packet4cf pmul<Packet4cf>(const Packet4cf& a, const Packet4cf& b)
    {
        __m256 tmp1 = _mm256_mul_ps(_mm256_moveldup_ps(a.v), b.v);
        __m256 tmp2 = _mm256_mul_ps(_mm256_movehdup_ps(a.v), _mm256_permute_ps(b.v, _MM_SHUFFLE(2, 3, 0, 1)));
        __m256 result = _mm256_addsub_ps(tmp1, tmp2);
        return Packet4cf(result);
    }

    template <> EIGEN_STRONG_INLINE Packet4cf pcmp_eq(const Packet4cf& a, const Packet4cf& b)
    {
        __m256 eq = _mm256_cmp_ps(a.v, b.v, _CMP_EQ_OQ);
        return Packet4cf(_mm256_and_ps(eq, _mm256_permute_ps(eq, 0xb1)));
    }

    template <> EIGEN_STRONG_INLINE Packet4cf ptrue<Packet4cf>(const Packet4cf& a) { return Packet4cf(ptrue(Packet8f(a.v))); }
    template <> EIGEN_STRONG_INLINE Packet4cf pand<Packet4cf>(const Packet4cf& a, const Packet4cf& b) { return Packet4cf(_mm256_and_ps(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet4cf por<Packet4cf>(const Packet4cf& a, const Packet4cf& b) { return Packet4cf(_mm256_or_ps(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet4cf pxor<Packet4cf>(const Packet4cf& a, const Packet4cf& b) { return Packet4cf(_mm256_xor_ps(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet4cf pandnot<Packet4cf>(const Packet4cf& a, const Packet4cf& b) { return Packet4cf(_mm256_andnot_ps(b.v, a.v)); }

    template <> EIGEN_STRONG_INLINE Packet4cf pload<Packet4cf>(const std::complex<float>* from)
    {
        EIGEN_DEBUG_ALIGNED_LOAD return Packet4cf(pload<Packet8f>(&numext::real_ref(*from)));
    }
    template <> EIGEN_STRONG_INLINE Packet4cf ploadu<Packet4cf>(const std::complex<float>* from)
    {
        EIGEN_DEBUG_UNALIGNED_LOAD return Packet4cf(ploadu<Packet8f>(&numext::real_ref(*from)));
    }

    template <> EIGEN_STRONG_INLINE Packet4cf pset1<Packet4cf>(const std::complex<float>& from)
    {
        return Packet4cf(_mm256_castpd_ps(_mm256_broadcast_sd((const double*)(const void*)&from)));
    }

    template <> EIGEN_STRONG_INLINE Packet4cf ploaddup<Packet4cf>(const std::complex<float>* from)
    {
        // FIXME The following might be optimized using _mm256_movedup_pd
        Packet2cf a = ploaddup<Packet2cf>(from);
        Packet2cf b = ploaddup<Packet2cf>(from + 1);
        return Packet4cf(_mm256_insertf128_ps(_mm256_castps128_ps256(a.v), b.v, 1));
    }

    template <> EIGEN_STRONG_INLINE void pstore<std::complex<float>>(std::complex<float>* to, const Packet4cf& from)
    {
        EIGEN_DEBUG_ALIGNED_STORE pstore(&numext::real_ref(*to), from.v);
    }
    template <> EIGEN_STRONG_INLINE void pstoreu<std::complex<float>>(std::complex<float>* to, const Packet4cf& from)
    {
        EIGEN_DEBUG_UNALIGNED_STORE pstoreu(&numext::real_ref(*to), from.v);
    }

    template <> EIGEN_DEVICE_FUNC inline Packet4cf pgather<std::complex<float>, Packet4cf>(const std::complex<float>* from, Index stride)
    {
        return Packet4cf(_mm256_set_ps(std::imag(from[3 * stride]),
                                       std::real(from[3 * stride]),
                                       std::imag(from[2 * stride]),
                                       std::real(from[2 * stride]),
                                       std::imag(from[1 * stride]),
                                       std::real(from[1 * stride]),
                                       std::imag(from[0 * stride]),
                                       std::real(from[0 * stride])));
    }

    template <> EIGEN_DEVICE_FUNC inline void pscatter<std::complex<float>, Packet4cf>(std::complex<float>* to, const Packet4cf& from, Index stride)
    {
        __m128 low = _mm256_extractf128_ps(from.v, 0);
        to[stride * 0] = std::complex<float>(_mm_cvtss_f32(_mm_shuffle_ps(low, low, 0)), _mm_cvtss_f32(_mm_shuffle_ps(low, low, 1)));
        to[stride * 1] = std::complex<float>(_mm_cvtss_f32(_mm_shuffle_ps(low, low, 2)), _mm_cvtss_f32(_mm_shuffle_ps(low, low, 3)));

        __m128 high = _mm256_extractf128_ps(from.v, 1);
        to[stride * 2] = std::complex<float>(_mm_cvtss_f32(_mm_shuffle_ps(high, high, 0)), _mm_cvtss_f32(_mm_shuffle_ps(high, high, 1)));
        to[stride * 3] = std::complex<float>(_mm_cvtss_f32(_mm_shuffle_ps(high, high, 2)), _mm_cvtss_f32(_mm_shuffle_ps(high, high, 3)));
    }

    template <> EIGEN_STRONG_INLINE std::complex<float> pfirst<Packet4cf>(const Packet4cf& a) { return pfirst(Packet2cf(_mm256_castps256_ps128(a.v))); }

    template <> EIGEN_STRONG_INLINE Packet4cf preverse(const Packet4cf& a)
    {
        __m128 low = _mm256_extractf128_ps(a.v, 0);
        __m128 high = _mm256_extractf128_ps(a.v, 1);
        __m128d lowd = _mm_castps_pd(low);
        __m128d highd = _mm_castps_pd(high);
        low = _mm_castpd_ps(_mm_shuffle_pd(lowd, lowd, 0x1));
        high = _mm_castpd_ps(_mm_shuffle_pd(highd, highd, 0x1));
        __m256 result = _mm256_setzero_ps();
        result = _mm256_insertf128_ps(result, low, 1);
        result = _mm256_insertf128_ps(result, high, 0);
        return Packet4cf(result);
    }

    template <> EIGEN_STRONG_INLINE std::complex<float> predux<Packet4cf>(const Packet4cf& a)
    {
        return predux(padd(Packet2cf(_mm256_extractf128_ps(a.v, 0)), Packet2cf(_mm256_extractf128_ps(a.v, 1))));
    }

    template <> EIGEN_STRONG_INLINE std::complex<float> predux_mul<Packet4cf>(const Packet4cf& a)
    {
        return predux_mul(pmul(Packet2cf(_mm256_extractf128_ps(a.v, 0)), Packet2cf(_mm256_extractf128_ps(a.v, 1))));
    }

    EIGEN_MAKE_CONJ_HELPER_CPLX_REAL(Packet4cf, Packet8f)

    template <> EIGEN_STRONG_INLINE Packet4cf pdiv<Packet4cf>(const Packet4cf& a, const Packet4cf& b)
    {
        Packet4cf num = pmul(a, pconj(b));
        __m256 tmp = _mm256_mul_ps(b.v, b.v);
        __m256 tmp2 = _mm256_shuffle_ps(tmp, tmp, 0xB1);
        __m256 denom = _mm256_add_ps(tmp, tmp2);
        return Packet4cf(_mm256_div_ps(num.v, denom));
    }

    template <> EIGEN_STRONG_INLINE Packet4cf pcplxflip<Packet4cf>(const Packet4cf& x)
    {
        return Packet4cf(_mm256_shuffle_ps(x.v, x.v, _MM_SHUFFLE(2, 3, 0, 1)));
    }

    //---------- double ----------
    struct Packet2cd
    {
        EIGEN_STRONG_INLINE Packet2cd() {}
        EIGEN_STRONG_INLINE explicit Packet2cd(const __m256d& a) : v(a) {}
        __m256d v;
    };

#ifndef EIGEN_VECTORIZE_AVX512
    template <> struct packet_traits<std::complex<double>> : default_packet_traits
    {
        typedef Packet2cd type;
        typedef Packet1cd half;
        enum
        {
            Vectorizable = 1,
            AlignedOnScalar = 0,
            size = 2,
            HasHalfPacket = 1,

            HasAdd = 1,
            HasSub = 1,
            HasMul = 1,
            HasDiv = 1,
            HasNegate = 1,
            HasSqrt = 1,
            HasAbs = 0,
            HasAbs2 = 0,
            HasMin = 0,
            HasMax = 0,
            HasSetLinear = 0
        };
    };
#endif

    template <> struct unpacket_traits<Packet2cd>
    {
        typedef std::complex<double> type;
        typedef Packet1cd half;
        typedef Packet4d as_real;
        enum
        {
            size = 2,
            alignment = Aligned32,
            vectorizable = true,
            masked_load_available = false,
            masked_store_available = false
        };
    };

    template <> EIGEN_STRONG_INLINE Packet2cd padd<Packet2cd>(const Packet2cd& a, const Packet2cd& b) { return Packet2cd(_mm256_add_pd(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet2cd psub<Packet2cd>(const Packet2cd& a, const Packet2cd& b) { return Packet2cd(_mm256_sub_pd(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet2cd pnegate(const Packet2cd& a) { return Packet2cd(pnegate(a.v)); }
    template <> EIGEN_STRONG_INLINE Packet2cd pconj(const Packet2cd& a)
    {
        const __m256d mask = _mm256_castsi256_pd(_mm256_set_epi32(0x80000000, 0x0, 0x0, 0x0, 0x80000000, 0x0, 0x0, 0x0));
        return Packet2cd(_mm256_xor_pd(a.v, mask));
    }

    template <> EIGEN_STRONG_INLINE Packet2cd pmul<Packet2cd>(const Packet2cd& a, const Packet2cd& b)
    {
        __m256d tmp1 = _mm256_shuffle_pd(a.v, a.v, 0x0);
        __m256d even = _mm256_mul_pd(tmp1, b.v);
        __m256d tmp2 = _mm256_shuffle_pd(a.v, a.v, 0xF);
        __m256d tmp3 = _mm256_shuffle_pd(b.v, b.v, 0x5);
        __m256d odd = _mm256_mul_pd(tmp2, tmp3);
        return Packet2cd(_mm256_addsub_pd(even, odd));
    }

    template <> EIGEN_STRONG_INLINE Packet2cd pcmp_eq(const Packet2cd& a, const Packet2cd& b)
    {
        __m256d eq = _mm256_cmp_pd(a.v, b.v, _CMP_EQ_OQ);
        return Packet2cd(pand(eq, _mm256_permute_pd(eq, 0x5)));
    }

    template <> EIGEN_STRONG_INLINE Packet2cd ptrue<Packet2cd>(const Packet2cd& a) { return Packet2cd(ptrue(Packet4d(a.v))); }
    template <> EIGEN_STRONG_INLINE Packet2cd pand<Packet2cd>(const Packet2cd& a, const Packet2cd& b) { return Packet2cd(_mm256_and_pd(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet2cd por<Packet2cd>(const Packet2cd& a, const Packet2cd& b) { return Packet2cd(_mm256_or_pd(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet2cd pxor<Packet2cd>(const Packet2cd& a, const Packet2cd& b) { return Packet2cd(_mm256_xor_pd(a.v, b.v)); }
    template <> EIGEN_STRONG_INLINE Packet2cd pandnot<Packet2cd>(const Packet2cd& a, const Packet2cd& b) { return Packet2cd(_mm256_andnot_pd(b.v, a.v)); }

    template <> EIGEN_STRONG_INLINE Packet2cd pload<Packet2cd>(const std::complex<double>* from)
    {
        EIGEN_DEBUG_ALIGNED_LOAD return Packet2cd(pload<Packet4d>((const double*)from));
    }
    template <> EIGEN_STRONG_INLINE Packet2cd ploadu<Packet2cd>(const std::complex<double>* from)
    {
        EIGEN_DEBUG_UNALIGNED_LOAD return Packet2cd(ploadu<Packet4d>((const double*)from));
    }

    template <> EIGEN_STRONG_INLINE Packet2cd pset1<Packet2cd>(const std::complex<double>& from)
    {
        // in case casting to a __m128d* is really not safe, then we can still fallback to this version: (much slower though)
        //   return Packet2cd(_mm256_loadu2_m128d((const double*)&from,(const double*)&from));
        return Packet2cd(_mm256_broadcast_pd((const __m128d*)(const void*)&from));
    }

    template <> EIGEN_STRONG_INLINE Packet2cd ploaddup<Packet2cd>(const std::complex<double>* from) { return pset1<Packet2cd>(*from); }

    template <> EIGEN_STRONG_INLINE void pstore<std::complex<double>>(std::complex<double>* to, const Packet2cd& from)
    {
        EIGEN_DEBUG_ALIGNED_STORE pstore((double*)to, from.v);
    }
    template <> EIGEN_STRONG_INLINE void pstoreu<std::complex<double>>(std::complex<double>* to, const Packet2cd& from)
    {
        EIGEN_DEBUG_UNALIGNED_STORE pstoreu((double*)to, from.v);
    }

    template <> EIGEN_DEVICE_FUNC inline Packet2cd pgather<std::complex<double>, Packet2cd>(const std::complex<double>* from, Index stride)
    {
        return Packet2cd(_mm256_set_pd(std::imag(from[1 * stride]), std::real(from[1 * stride]), std::imag(from[0 * stride]), std::real(from[0 * stride])));
    }

    template <> EIGEN_DEVICE_FUNC inline void pscatter<std::complex<double>, Packet2cd>(std::complex<double>* to, const Packet2cd& from, Index stride)
    {
        __m128d low = _mm256_extractf128_pd(from.v, 0);
        to[stride * 0] = std::complex<double>(_mm_cvtsd_f64(low), _mm_cvtsd_f64(_mm_shuffle_pd(low, low, 1)));
        __m128d high = _mm256_extractf128_pd(from.v, 1);
        to[stride * 1] = std::complex<double>(_mm_cvtsd_f64(high), _mm_cvtsd_f64(_mm_shuffle_pd(high, high, 1)));
    }

    template <> EIGEN_STRONG_INLINE std::complex<double> pfirst<Packet2cd>(const Packet2cd& a)
    {
        __m128d low = _mm256_extractf128_pd(a.v, 0);
        EIGEN_ALIGN16 double res[2];
        _mm_store_pd(res, low);
        return std::complex<double>(res[0], res[1]);
    }

    template <> EIGEN_STRONG_INLINE Packet2cd preverse(const Packet2cd& a)
    {
        __m256d result = _mm256_permute2f128_pd(a.v, a.v, 1);
        return Packet2cd(result);
    }

    template <> EIGEN_STRONG_INLINE std::complex<double> predux<Packet2cd>(const Packet2cd& a)
    {
        return predux(padd(Packet1cd(_mm256_extractf128_pd(a.v, 0)), Packet1cd(_mm256_extractf128_pd(a.v, 1))));
    }

    template <> EIGEN_STRONG_INLINE std::complex<double> predux_mul<Packet2cd>(const Packet2cd& a)
    {
        return predux(pmul(Packet1cd(_mm256_extractf128_pd(a.v, 0)), Packet1cd(_mm256_extractf128_pd(a.v, 1))));
    }

    EIGEN_MAKE_CONJ_HELPER_CPLX_REAL(Packet2cd, Packet4d)

    template <> EIGEN_STRONG_INLINE Packet2cd pdiv<Packet2cd>(const Packet2cd& a, const Packet2cd& b)
    {
        Packet2cd num = pmul(a, pconj(b));
        __m256d tmp = _mm256_mul_pd(b.v, b.v);
        __m256d denom = _mm256_hadd_pd(tmp, tmp);
        return Packet2cd(_mm256_div_pd(num.v, denom));
    }

    template <> EIGEN_STRONG_INLINE Packet2cd pcplxflip<Packet2cd>(const Packet2cd& x) { return Packet2cd(_mm256_shuffle_pd(x.v, x.v, 0x5)); }

    EIGEN_DEVICE_FUNC inline void ptranspose(PacketBlock<Packet4cf, 4>& kernel)
    {
        __m256d P0 = _mm256_castps_pd(kernel.packet[0].v);
        __m256d P1 = _mm256_castps_pd(kernel.packet[1].v);
        __m256d P2 = _mm256_castps_pd(kernel.packet[2].v);
        __m256d P3 = _mm256_castps_pd(kernel.packet[3].v);

        __m256d T0 = _mm256_shuffle_pd(P0, P1, 15);
        __m256d T1 = _mm256_shuffle_pd(P0, P1, 0);
        __m256d T2 = _mm256_shuffle_pd(P2, P3, 15);
        __m256d T3 = _mm256_shuffle_pd(P2, P3, 0);

        kernel.packet[1].v = _mm256_castpd_ps(_mm256_permute2f128_pd(T0, T2, 32));
        kernel.packet[3].v = _mm256_castpd_ps(_mm256_permute2f128_pd(T0, T2, 49));
        kernel.packet[0].v = _mm256_castpd_ps(_mm256_permute2f128_pd(T1, T3, 32));
        kernel.packet[2].v = _mm256_castpd_ps(_mm256_permute2f128_pd(T1, T3, 49));
    }

    EIGEN_DEVICE_FUNC inline void ptranspose(PacketBlock<Packet2cd, 2>& kernel)
    {
        __m256d tmp = _mm256_permute2f128_pd(kernel.packet[0].v, kernel.packet[1].v, 0 + (2 << 4));
        kernel.packet[1].v = _mm256_permute2f128_pd(kernel.packet[0].v, kernel.packet[1].v, 1 + (3 << 4));
        kernel.packet[0].v = tmp;
    }

    template <> EIGEN_STRONG_INLINE Packet2cd psqrt<Packet2cd>(const Packet2cd& a) { return psqrt_complex<Packet2cd>(a); }

    template <> EIGEN_STRONG_INLINE Packet4cf psqrt<Packet4cf>(const Packet4cf& a) { return psqrt_complex<Packet4cf>(a); }

}  // end namespace internal

}  // end namespace Eigen

#endif  // EIGEN_COMPLEX_AVX_H
